A fungal outbreak in Tennessee has drawn national attention after at least 35 people became sick and one death is under investigation. Health officials say the illnesses are linked to histoplasmosis, a lung infection caused by a fungus commonly found in soil. The outbreak highlights how everyday activities like construction, yard work, and excavation can pose unexpected health risks, especially in certain regions of the United States.
This article explains what histoplasmosis is, how it spreads, who is most at risk, and what residents in affected areas should know to protect themselves.
Histoplasmosis is an infection caused by breathing in spores of a fungus called Histoplasma capsulatum. The fungus lives in soil, particularly soil that contains bird or bat droppings. When soil is disturbed, microscopic spores can become airborne and inhaled into the lungs.
The infection primarily affects the respiratory system. In many cases, people experience mild symptoms or no symptoms at all. However, some individuals develop severe lung disease and complications that can be life threatening if not treated.
According to the U.S. Centers for Disease Control and Prevention, histoplasmosis is most common in areas along the Ohio and Mississippi River valleys, which include large portions of Tennessee.
In January 2026, Tennessee health officials confirmed an increase in histoplasmosis cases, with at least 35 people becoming ill. The outbreak is centered in Maury and Williamson counties, south of Nashville, particularly in the towns of Spring Hill and Thompson’s Station.
The Tennessee Department of Health reported a rise in severe cases beginning in September 2025. One death is under review, with an autopsy underway to confirm whether histoplasmosis was the cause.
The CDC is providing technical support as state health officials investigate potential exposure sources and patterns.
One of the people affected was Alyssia Brown, a 39 year old woman from Spring Hill. According to her family, she began feeling ill in October. Initial tests for flu and COVID were negative, and early imaging did not show lung abnormalities.
Without health insurance, Brown delayed seeking further care. Her condition worsened over several weeks. In December, she went to the emergency room, where doctors tested her for histoplasmosis. She was found dead in her bedroom on December 15, before the test results were returned. Her family learned days later that the test was positive.
Family members told reporters that Brown had noticed extensive construction and excavation in areas where she regularly drove. Her death has raised concerns about how environmental disruption may contribute to fungal exposure.
Histoplasmosis does not spread from person to person or from animals to humans. Infection occurs only through inhalation of fungal spores from the environment.
Common activities associated with exposure include:
The Tennessee Department of Health noted that the fungus is commonly found throughout the state, making it difficult to completely prevent exposure.
Symptoms usually appear between three days and two weeks after exposure. The illness often resembles the flu, which can delay diagnosis.
Common symptoms include:
Most people recover without treatment, but symptoms can persist for weeks or months in some cases.
In severe cases, histoplasmosis can spread beyond the lungs to other organs, leading to serious complications.
Experts estimate that up to 90 percent of people living in endemic regions may be exposed to the fungus at some point in their lives, yet most never become seriously ill.
Higher risk groups include:
Dr. Lili Tao of Vanderbilt University Medical Center stated that most cases are mild and treatable, but severe infections can occur depending on exposure level and immune health.
Diagnosing histoplasmosis can be challenging because symptoms overlap with other respiratory illnesses. Doctors may use blood tests, urine tests, imaging studies, or tissue samples to confirm infection.
Mild cases often resolve without medication. More severe infections may require antifungal treatment, sometimes for several months.
Early diagnosis improves outcomes, especially for people at higher risk of complications.
The outbreak has drawn attention to the role of construction and land development in fungal exposure. Disturbing soil releases spores into the air, increasing the risk for nearby residents and workers.
Rapid growth in areas south of Nashville has led to extensive excavation, demolition, and infrastructure projects. Health officials are examining whether these activities contributed to the rise in cases.
Similar outbreaks linked to construction have been documented as far back as the 1930s, with case numbers ranging from a few individuals to several hundred.
The Tennessee Department of Health has asked healthcare providers to report any patients with symptoms consistent with histoplasmosis who test positive or may be linked to known cases.
Public health authorities are also working to identify common exposure sources and raise awareness among residents and clinicians.
The CDC is assisting with epidemiological analysis and guidance.
While it is not possible to eliminate exposure entirely in endemic areas, certain precautions may reduce risk:
People with weakened immune systems should talk to their healthcare provider about additional precautions.
You should contact a healthcare provider if you experience:
Early evaluation can help prevent complications and guide appropriate treatment.
The Tennessee histoplasmosis outbreak underscores the importance of environmental awareness and early medical evaluation. While most exposures do not lead to illness, increased development and population growth in endemic regions may raise the likelihood of future outbreaks.
Public education, healthcare provider awareness, and timely reporting remain essential tools in protecting community health.
Histoplasmosis is a well known but often overlooked fungal infection that can become serious under the right conditions. The recent Tennessee outbreak serves as a reminder that soil borne diseases remain a public health concern, especially in areas undergoing rapid construction and land disturbance.
By understanding how the disease spreads, recognizing symptoms early, and taking reasonable precautions, individuals and communities can reduce risk and improve outcomes.
This article is for informational and educational purposes only and is not intended as medical advice, diagnosis, or treatment. Health information reflects general trends and may not apply to individual circumstances. Always consult a qualified healthcare professional for personalized medical guidance.
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